# cdimascio/express-openapi-validator

🦋 Auto-validates api requests, responses, and securities using ExpressJS and an OpenAPI 3.1.x or 3.0.x specification

Repository: https://github.com/cdimascio/express-openapi-validator
Canonical: https://ross.abutalabs.com/products/express-openapi-validator
Language: TypeScript
License: MIT
License Family: permissive
Topics: openapi3, express-middleware, nodejs, request-validation, expressjs, middleware, rest-api, express, openapi, connect-middleware, hacktoberfest, openapi-validator
Last push: 2026-09-03T00:36:13+00:00

## Health v2 (maintenance only)
Score: 88/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 100, release rhythm 66, longevity 100
- inputs: {"age_days": 2724, "days_push": 0, "days_rel": 226, "gap_med": 6, "n_releases_24m": 24}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1005, forks 238 (observed 2026-09-03T02:15:09.891070+00:00)

## What it is
An Express middleware library that automatically validates API requests, responses, and security against an OpenAPI 3.0.x or 3.1.x specification. It integrates unopinionatedly with new or existing Express apps and can optionally map OpenAPI endpoints to handler functions.

## Use cases
- validate express api requests against an openapi spec
- auto-validate api responses with openapi 3
- enforce security schemes on express routes
- validate file uploads in a rest api
- split openapi spec across multiple files with $ref
- add openapi validation to an existing express app

## When to choose
- you have an Express 4 or 5 REST API and want spec-driven validation without changing your project structure
- you want request, response, and security validation from a single OpenAPI 3.0/3.1 document
- you need custom formats, serializers, or security handler support

## When to avoid
- your API is not built on Express or Connect-compatible middleware
- you need non-JSON response validation
- you use a framework with built-in OpenAPI validation

## Facets
- artifact type: library
- maturity: active
- function: middleware, api-framework, security, serialization
- domain: web-development, backend, apis, developer-tools
- platform: -
- tags: openapi, express, request-validation, response-validation, rest-api, openapi-3, typescript, nodejs, web-server

## Member repositories
- cdimascio/express-openapi-validator (main) score 88

## Provenance
- Observed fields: from GitHub, fetched 2026-09-03T02:15:09.891070+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T07:13:08.979249+00:00, confidence not recorded.
  - readme: https://github.com/cdimascio/express-openapi-validator (fetched 2026-09-03T02:15:09.891070+00:00, sha 0f3b7781cca4)
- Data as of 2026-08-30T08:39:29.467469+00:00.